1. Technical Field
This invention relates to new and useful improvements in the molding of foam materials More specifically, the invention relates to a mold for rebonding foam.
2. Description of the Related Art
Articles of foam have long been used for padding and support in a wide variety of articles of furniture and the foam articles are typically formed by a molding operation. As shown in the U.S. Pat. No. 3,124,627 to Hood (issued Jan. 13, 1961), it is known to produce and cure such articles through the use of a heated mold where the heat is supplied to the mold in the form of steam.
It is also known to recycle polyurethane foam such that the waste foam is ground up and rebonded to create a new foamed article. As shown in U.S. Pat. No. 4,591,469 to Buchanan, et al. (issued May 27, 1986), rebonding of polyurethane foam can be accomplished by shredding and grinding the foam, blending the waste foam with a flexible polyurethane foam-forming formulation and other solid materials. Thereafter, the mixture is subjected to curing in a steam-heated mold.
The molding operations previously known incorporate a mold constructed of highly durable and corrosive resistant material such as aluminum. In addition to the high cost of such materials, these materials are limited in the configurations which may be easily created. Use of materials such as aluminum, rather than materials such as epoxy is dictated by the relative pressure of the steam for curing required for the known mold configurations. With relative high steam pressures in the mold, use of materials such as epoxy can result in leaks of water and steam from the joints and openings of the mold.